1. Field of the Invention
The present invention relates to an apparatus for supplying electric components (i.e., circuit components used for providing electric circuits (e.g., electronic circuits)), and a method of assembling an electric circuit on a print-wired board, i.e., a circuit board, and in particular to the art of improving the supplying of electric components from an electric-component tape holding the electric components.
2. Related Art Statement
There is known an electric-component (xe2x80x9cECxe2x80x9d) tape which includes a carrier tape and which holds a plurality of electric components (xe2x80x9cECsxe2x80x9d) at a predetermined pitch in a lengthwise direction of the carrier tape, and there is known an EC supplying device which supplies ECs from an EC tape holding the ECs. The EC supplying device includes a feeding device which feeds the EC tape in its lengthwise direction so that the ECs are supplied, one by one, to an object device. If the ECs are supplied one after another and the EC tape is consumed near to the end, an operator connects an initial end portion of another EC tape to a terminal end portion of the current EC tape now supplying the ECs, before the ECs of the current tape are completely consumed. Thus, the ECs of the new tape are successively supplied after the ECs of the preceding tape, without interruption, as if the ECs were supplied limitlessly.
It is therefore an object of the present invention to provide an electric-component supplying apparatus, an electric-component supplying system, and a circuit-board assembling method each of which detects a connection portion where two electric-component tapes are connected to each other and which can utilize the detected connection portion.
The present invention provides an electric-component supplying apparatus, an electric-component supplying system, and a circuit-board assembling method which have one or more of the technical features that are described below in respective paragraphs given parenthesized sequential numbers (1) to (27). Any technical feature which includes another technical feature shall do so by referring, at the beginning, to the parenthesized sequential number given to that technical feature. Thus, two or more of the following technical features may be combined, if appropriate. Each technical feature may be accompanied by a supplemental explanation, as needed. However, the following technical features and the appropriate combinations thereof are just examples to which the present invention is by no means limited.
(1) According to a first feature of the present invention, there is provided an apparatus for feeding a plurality of electric-component tapes each of which includes a carrier tape and holds a plurality of electric components in a lengthwise direction of the carrier tape, and supplying, from the each electric-component tape, the electric components, one by one, to an object device, the apparatus comprising: a feeding device which feeds a first electric-component tape in a lengthwise direction thereof; and a connection-portion detecting device which detects a connection portion where a terminal end portion of the first electric-component tape being fed by the feeding device is connected to an initial end portion of a second electric-component tape. The EC tape may be an embossed-carrier-type one, a punched-carrier-tape one, or a lead-wire-terminal-taped-type one. The embossed-carrier-type EC tape includes (a) a carrier tape which includes a pair of widthwise opposite end portions each extending in a lengthwise direction thereof, and a plurality of embossed portions each projecting downward from between the two end portions and each accommodating one EC, and (b) a top cover tape which is adhered to the carrier tape to close respective upper openings of the embossed portions. The punched-carrier-tape EC tape includes (c) a carrier tape which includes (c1) a base tape which is formed of, e.g., paper or synthetic resin and which has a plurality of through-holes formed through the thickness thereof and (c2) a bottom cover tape which closes respective lower openings of the through-holes to provide a plurality of EC accommodating pockets each accommodating one EC, and (d) a top cover tape which is adhered to the carrier tape to close respective upper openings of the through-holes or the EC accommodating pockets. The lead-wire-terminal-taped-type EC tape may be one which includes a carrier tape which is provided by a tacky tape and which holds a plurality of electric components whose respective lead-wire terminals are adhered thereto, or one which includes a carrier tape which includes a tacky tape and a support sheet and which holds a plurality of electric components whose respective lead-wire terminals are adhered thereto. The second EC tape may be a new one from which no ECs have not been taken, or a used one from which one or more ECs have been taken. The first and second EC tapes to be connected to each other must at least be of a same type, e.g., both of the embossed-carrier type, the punched-carrier tape, or the lead-wire-terminal-taped type, and must hold a same sort of ECs. The object device to which the present EC supplying apparatus supplies the ECs may be an EC mounting system as an element of a circuit-board (xe2x80x9cCBxe2x80x9d) assembling system, or an EC transferring device which transfers ECs from the EC supplying apparatus to a third device. However, the EC mounting system can be said as a sort of EC transferring device, because it transfers ECs from the EC supplying apparatus to respective EC-mount places on a print-wired board (xe2x80x9cPWBxe2x80x9d). The present EC supplying apparatus detects the connection portion of the two EC tapes connected to each other. Accordingly, for example, the present apparatus can judge whether the second EC tape actually connected to the first EC tape is a correct sort of EC tape to be connected to the first tape, and can monitor the amount of ECs remaining on the first EC tape, or the first and second EC tapes connected to each other.
(2) According to a second feature of the present invention that includes the first feature (1), the supplying apparatus further comprises a frame including a guide which guides the movement of each of the first and second electric-component tapes in the lengthwise direction thereof, and the connection-portion detecting device is supported by the frame in vicinity of a path of movement of the each electric-component tape. The connection-portion detecting device may be provided on the path of movement of each EC tape, or at a location somewhat distant from the path. In the case where the connection-portion detecting device is provided at a location largely distant from the path defined by the guide, each EC tape must take a circuitous route for the connection portion to be detected by the detecting device. In contrast, in the case where the connection-portion detecting device is provided in the vicinity of the path, the detecting device can directly detect the connection portion while each EC tape is moved on the path defined by the guide. In the latter case, a smaller space is needed for the movement of the EC tape, which contributes to reducing the overall size of the present EC supplying apparatus.
(3) According to a third feature of the present invention that includes the first or second feature (1) or (2), the connection-portion detecting device comprises a metal detector which detects a metallic connection member which connects the terminal end portion of the first electric-component tape and the initial end portion of the second electric-component tape to each other. The metallic connection member is formed of, e.g., steel, copper, brass, SUS, or aluminum. The connection member cooperates with the the terminal and initial end portions of the two EC tapes to provide the connection portion. The metal detector detects the connection member and thereby detects the connection portion.
(4) According to a fourth feature of the present invention that includes the third feature (3), the metal detector comprises a pair of electrodes which are distant from each other on a locus of movement of the metallic connection member when the two electric-component tapes connected to each other are fed in the lengthwise direction thereof, and which are electrically connected to each other by the metallic connection member; and a connection detecting circuit which electrically detects that the two electrodes are connected to each other by the metallic connection member. If the supplying of the ECs progresses after the connection of the two EC tapes, the metallic connection member eventually reaches the pair of electrodes, moves along the same, and contacts both of the same, thereby electrically connecting the same to each other. The connection detecting circuit produces a first signal when the two electrodes are electrically connected, and a second signal different from the first signal, when the two electrodes are not connected. Thus, the production of the first signal from the connection detecting circuit indicates that the metallic connection member is moving on the electrodes. In this way, the connection portion can be detected.
(5) According to a fifth feature of the present invention that includes the fourth feature (4), the connection-portion detecting device further comprises a pressing member which presses the metallic connection member against the two electrodes. Since the metallic connection member is positively pressed against the pair of electrodes by the pressing member, the two electrodes can be more reliably connected to each other by the metallic connection member. Thus, the metallic connection member or the connection portion can be more reliably detected.
(6) According to a sixth feature of the present invention that includes the fifth feature (5), the pressing member comprises a pressing roller which is movable toward, and away from, the metallic connection member, and which is rotatable about an axis line intersecting a direction of feeding of the two electric-component tapes connected to each other. Since the pressing roller presses the metallic connection member against the pair of electrodes while being rotated by the movement of the EC tape, the EC tape is subjected to only a low resistance to its movement.
(7) According to a seventh feature of the present invention that includes the fifth or sixth feature (5) or (6), the connection-portion detecting device further comprises a biasing device which biases the pressing member in a direction in which the pressing member is moved toward the two electrodes. The biasing device may be the self weight of the pressing member, or the sum of the self weight of the pressing member and that of a support member which supports the pressing member. Alternatively, the biasing device may be provided by a spring member as a sort of elastic member. The employment of the biasing device further improves the reliability with which the pair of electrodes are connected to each other.
(8) According to an eighth feature of the present invention that includes the third feature (3), the metal detector comprises a non-contact sensor which detects the metallic connection member, without contacting the connection member. Since the non-contact sensor does not contact the connection member, the sensor is prevented from wearing and accordingly enjoys a long life expectancy.
(9) According to a ninth feature of the present invention that includes the eighth feature (8), the non-contact sensor comprises an induction proximity sensor. The induction proximity sensor may be a high-frequency proximity sensor. However, it is possible to use a different sort of non-contact sensor, such as a capacitance proximity sensor.
(10) According to a tenth feature of the present invention that includes the first or second feature (1) or (2), the connection-portion detecting device comprises an optical detector which detects the connection portion of the two electric-component tapes, based on a difference between an optical characteristic of the connection portion and an optical characteristic of respective remaining portions of the two tapes. The optical characteristic may be a color, a reflection factor, or a transparency. If there is a detectable difference between the optical characteristic of the connection portion and that of the respective remaining portions of the two EC tapes, the connection portion can be detected by the optical detector which can detect the difference.
(11) According to an eleventh feature of the present invention that includes the tenth feature (10), the optical detector comprises a light emitter which emits a light toward a portion of the connected electric-component tapes; a light receiver which receives the light which has been emitted by the light emitter and optically affected by the portion of the connected electric-component tapes; and a judging device which judges, based on a change of the light received by the light receiver from the light emitted by the light emitter, whether the portion of the connected electric-component tapes is the connection portion thereof. The light receiver may be one which receives the light which has been reflected by each EC tape, or one which receives the light which has been transmitted by each EC tape. The affection to the light by each EC tape may be the change of amount of the reflected or transmitted light, or the change of frequency component of the reflected or transmitted light. The latter optical affection may be detected by, e.g., a color sensor. In the case where the light receiver is one which receives the light reflected by each EC tape, the respective colors or reflection factors of each carrier tape and the connection member are so predetermined as to produce a distinguishable difference between the respective amounts or frequency components of the respective lights reflected from the each carrier tape and the connection member. Each carrier tape, each top cover tape, and the connection member may be formed of any material, and the connection member may be formed of metal, or may be provided by a connection tape formed of a synthetic resin. The connection tape has a tacky material or an adhesive material on one major surface thereof, and may be adhered to the respective carrier tapes of the two EC tapes. In the case where each carrier tape is formed of a transparent synthetic resin, the connection member may be provided by a connection tape formed of an opaque synthetic resin, or a metallic connection member. In this case, the connection member significantly changes the amount of the light transmitted by the two EC tapes connected to each other. Therefore, a transmission-type photoelectric sensor can detect the connection portion of the connected EC tapes. In the case where each carrier tape and the connection tape have different colors, the connection portion can be detected based on a difference between the respective frequency components of the respective lights transmitted by the each carrier tape and the connection tape. All of the above explanation is true with each of the embossed-carrier-type EC tape, the punched-carrier-type EC tape, and the lead-wire-terminal-taped-type EC tape. However, it is preferred that how to combine the connection member or tape and the light emitter and receivers and where the connection member or tape is placed relative to the carrier tapes to be connected be so predetermined as not to be affected by the ECs held by the carrier tapes. Even if the light received by the light receiver may have been affected by the EC or ECs, it is possible to remove that affection because the ECs are regularly held at the predetermined pitch by the carrier tapes. However, to remove the affection is cumbersome, which may lead to lowering the reliability of detection of the connection portion.
(12) According to a twelfth feature of the present invention that includes any one of the first to eleventh features (1) to (11), the supplying apparatus further comprises a tape-connection-relating-information producing device which produces first information when the second electric-component tape is appropriate, and second information when the second tape is not appropriate. The second EC tape is not appropriate, e.g., when the sort of the ECs held by the second EC tape is different from that of the ECs held by the first EC tape being fed by the feeding device, or when the type (the embossed-carrier type, the punched-carrier type, or the lead-wire-terminal-taped type) the second tape is different from that of the first tape. The first or second information may be utilized in various manners. For example, in the case where the second information is produced, it may be informed to an operator so that the operator can avoid the supplying of the ECs held by the inappropriate EC tape.
(13) According to a thirteenth feature of the present invention that includes the twelfth feature (12), the tape-connection-relating-information producing device comprises an input device which inputs identification information identifying the second electric-component tape; and an inappropriate-tape-connection-information producing device which is connected to the input device and which compares, in response to the detection of the connection portion by the connection-portion detecting device, the identification information input by the input device, with reference identification information and, when the input identification information is not identical with the reference identification information, producing, as the second information, inappropriate-tape-connection information indicating that the input identification information is not identical with the reference identification information. Identification information identifying an EC tape may include the identification number of the ECs held by the EC tape; the dimensions of each EC; the total number of the ECs; the production date of the ECs; the electric characteristic values of the ECs; the width of each EC; the pitch at which the ECs are held by the EC tape; the type of the EC tape; and the width of the EC tape. The Identification information may be represented by a bar code. The input device may be one which automatically inputs the identification information; or one which is operable by an operator for inputting the identification information. The former input device may be provided by a bar-code reader which automatically reads in a bar code representing the identification information; and the latter input device may be provided by a bar-code reader which is manually operable by the operator for reading in the bar code. Alternatively, the latter input device may be provided by, e.g., a keyboard which is manually operable by the operator for inputting the identification information. The input identification information identifies the second EC tape actually connected to the first EC tape being fed by the feeding device for supplying the ECs. The reference identification information identifies another EC tape which should be connected to the first EC tape being fed by the feeding device for supplying the ECs. The reference identification information may be input by an operator through an appropriate input device such as a keyboard, or otherwise may be given to the EC supplying apparatus from a controller or a computer different from a controller of the supplying apparatus. If the two pieces of identification information are compared with each other and judged as being identical with each other means, then it is judged that the second EC tape is an EC tape which should be connected to the first EC tape. However, if not, the second tape is not an appropriate tape. In the latter case, the inappropriate-tape-connection information is produced, and is utilized to treat the inappropriate tape connection, e.g., stop the operation of the CB assembling system. That is, the present EC supplying apparatus can treat, based on the detection of the connection portion, the inappropriate tape connection.
(14) According to a fourteenth feature of the present invention that includes the thirteenth feature (13), the tape-connection-relating-information producing device further comprises an inappropriate-tape-connection informing device which informs, based the inappropriate-tape-connection information, an operator of at least a fact that the second electric-component tape is not appropriate. The informing device may inform the operator of the fact, in various manners, e.g., by generating an alarm sound, lighting or flashing a lamp, or displaying an alarm message on an image screen.
(15) According to a fifteenth feature of the present invention that includes any one of the first to fourteenth features (1) to (14), the supply apparatus further comprises an input device which inputs identification information identifying the second electric-component tape; and an input judging device which is connected to the input device and which judges, in response to the detection of the connection portion by the connection-portion detecting device, whether the identification information has been input by the input device. In the case where the input device is adapted to automatically input identification information when the second EC tape is connected to the first EC tape, there is little possibility that the input device should fail to input the identification information. However, in the case where an operator inputs identification information through the input device such as a bar-code reader or a keyboard, the operator may fail to input the identification information. In the latter case, even if an inappropriate EC tape may be connected to the first tape, no inappropriate-tape-connection information is produced, so that ECs may be supplied from the inappropriate EC tape. In contrast, in the present EC supplying apparatus, the input judging device judges, in response to the detection of the connection portion, whether the identification information has been input by the input device. In this case, the present EC supplying apparatus may inform the operator of the negative judgment that no identification information has been input, so that the operator can stop the feeding of the inappropriate EC tape or the supplying of inappropriate sort of ECs from that EC tape.
(16) According to a sixteenth feature of the present invention that includes the fifteenth feature (15), the supplying apparatus further comprises a non-input informing device which informs, when the input judging device judges that the identification information has not been input by the input device, an operator of a fact that the identification information has not been input by the input device. The non-input informing device may inform the operator of the fact, in various manners, e.g., by generating an alarm sound, lighting or flashing a lamp, or displaying an alarm message on an image screen.
(17) According to a seventeenth feature of the present invention that includes any one of the first to sixteenth features (1) to (16), the supplying apparatus further comprises an input device which inputs identification information identifying the second electric-component tape; and a connection-relating-input judging device which is connected to the input device and which judges whether the identification information has been input by the input device in relation with the connection of the first and second electric-component tapes to each other. For example, the identification information on which the input judging device according to the fifteenth feature (15) makes a judgment needs to be the identification information input in relation with the connection of the second EC tape to the first EC tape currently supplying the ECs. If, after the mounting of ECs on a PWB is started, identification information is input at a time different than when two EC tapes are connected to each other, or if the identification information input at the time of the prior connection of two tapes remains, the identification information should not be used for the judgment of the above input judging device. Hence, the present EC supplying apparatus employs the connection-relating-input judging device which judges whether the identification information has been input in relation with the connection of the second EC tape to the first EC tape currently supplying the ECs. The connection-relating-input judging device may be one which judges whether the identification information has been input within a reference time period. The reference time period may be somewhat longer than an average time period between the connection of two EC tapes and the detection of the connection portion of the two EC tapes. If the connection portion is detected within the reference time period after the inputting of identification information, a positive judgment is made. The reference time period may be determined based on a time needed for the connection portion to be fed from a tape-connect position where two tapes are connected to each other, to a connection-portion-detect position where the connection portion of the two tapes is detected. This time depends on the distance between the tape-connect position and the connection-portion-detect position (i.e, the length of the first EC tape between the connection portion and the connection-portion detecting device when the two tapes are connected to each other); the pitch at which the ECs are held by each EC tape; and the rate at which the EC supplying apparatus supplies the ECs (e.g., whether the supplying apparatus continuously or continually supplies the ECs). A plurality of reference time periods may be determined exclusively for a plurality of sorts of EC tapes, respectively, or a single reference time period may be determined commonly for a plurality of sorts of EC tapes. In the latter case, the single reference time period may be determined based on the longest one of the respective times needed for the respective connection portions of the different sorts of EC tapes to be fed from the tape-connect position to the connection-portion-detect position. The connection-relating-input judging device may be one which judges whether the identification information has been input within a time period needed for supplying a reference number of ECs. The reference number may be somewhat more than an average number of the ECs which are supplied between the connection of two EC tapes and the detection of the connection portion of the two tapes. In the latter case, the judging device makes a positive judgment if the number of the ECs supplied after the inputting of the identification information and before the detection of the connection portion of two tapes is smaller than the reference number. The reference number may be determined based on the distance between the tape-connect position and the connection-portion-detect position and the pitch at which the ECs are held by each EC tape. The connection-relating-input judging device may be omitted, e.g., in the case where no identification information is input except when two EC tapes are connected to each other, or in the case where even if identification information may be input at a time other than when two EC tapes are connected to each other, the input identification information is deleted without fail after being utilized. The connection-relating-input judging device may be employed in the EC supplying apparatus according to the thirteenth feature (13). In the last case, the inappropriate-tape-connection-information producing device is prevented from comparing the reference identification information with the identification information which has not been input in relation with the connection of two EC tapes, and producing the inappropriate-tape-connection information though the tape connection is appropriate, or vice versa.
(18) According to an eighteenth feature of the present invention that includes any one of the thirteenth to seventeenth features (13) to (17), the input device comprises a bar-code reader which reads in a bar code as the identification information identifying the second electric-component tape. Information relating to the second EC tape can be easily and quickly input by utilizing the bar code and the bar-code reader. The more the identification information is, the more advantageous the bar code and the bar-code reader are. The bar code may be automatically read in by the bar-code reader, or may be read in by an operator through the bar-code reader operated by the operator.
(19) According to a nineteenth feature of the present invention that includes any one of the first to eighteenth features (1) to (18), the supplying apparatus further comprises an electric-component counter which counts a number of electric components supplied by the apparatus after the connection-portion detecting device detects the connection portion. The EC counter can be used to control the supplying of the ECs. For example, in the case where the present EC supplying apparatus includes an initial-amount obtaining device which obtains, as an initial amount, an initial number of ECs which are initially present on the second EC tape newly connected to the first EC tape; and a subtracting device which subtracts the number counted by the EC counter, from the initial number obtained by the initial-amount obtaining device, the supplying apparatus can obtain the amount of the ECs which currently remain on the second EC tape. In the case where the second EC tape is a new one, the initial-amount obtaining device may obtain the initial amount of the ECs held by the new tape, from the identification information (e.g., bar code) input by the input device (e.g., bar-code reader). In the case where the second EC tape is a used one, the initial-amount obtaining device may obtain the initial amount of the ECs held by the used tape, from information other than the identification information identifying the used tape, for example, from the information that is input by the operator through a keyboard including numeric keys. The EC counter may be set at an initial number based on the initial amount obtained by the initial-amount obtaining device, and the initial number may be decreased by one by a subtracting device each time one EC is supplied. In the latter case, the current count number of the EC counter indicates the current amount of the ECs remaining on the second EC tape. Thus, the EC counter is used as a decreasing counter (or a remaining-amount counter). In the case where the EC supplying apparatus further includes a subtracting device which subtracts the remaining amount from the initial amount, the supplying apparatus can obtain the number of the ECs which have been supplied from the second EC tape. In the last case, the subtracting device also functions as a device which obtains the number of the supplied ECs.
(20) According to a twentieth feature of the present invention that includes any one of the first to eighteenth features (1) to (18), the supplying apparatus further comprises a counter which changes a count number by one each time one of the electric components is supplied by the apparatus; an initial-amount obtaining device which obtains, as an initial amount, an initial number of the electric components which are initially present on the second electric-component tape connected to the first electric-component tape; and a remaining-amount obtaining device which cooperates with the counter, the initial-amount obtaining device, and the connection-portion detecting device to obtain, as a remaining amount, a current number of the electric components which are currently present on the second electric-component tape. The counter may be an increasing counter which increases its count number, or a decreasing counter which decreases its count number. In the case where the counter is the increasing counter, the remaining-amount obtaining device sets the increasing counter to its initial count number, in response to the detection of the connection portion by the connection-portion detecting device, and obtains the remaining amount, as needed, by subtracting the current count number of the increasing counter, from the initial amount. The initial count number of the increasing counter may be zero in the case where the required accuracy of the remaining amount obtained by the remaining-amount obtaining device is low. However, in the case where the required accuracy is high, the increasing counter must be set to an initial count number equal to a number obtained by subtracting, from zero, the number of the ECs remaining between an EC-supply position of the EC supplying apparatus and the connection portion at the time of detection of the connection portion. Since, usually, the EC-supply position is distant from the connection-portion-detect position, the first EC tape being fed by the feeding device for supplying the ECs still has some remaining ECs between the two positions at the time of detection of the connection portion. Hence, in the case where there is the need to control accurately the amount of the ECs remaining on the second EC tape, the number of the ECs present on the first EC tape between the above two positions should be taken into account. The latter number can be estimated based on the length of the first EC tape between the above two positions and the pitch at which the ECs are held by the first tape. Meanwhile, in the case where the counter is the decreasing counter, the remaining-amount obtaining device sets, in response to the detection of the connection portion, the decreasing counter to an initial counter number based on the initial amount obtained by the initial-amount obtaining device, and reads out the current count number of the decreasing counter, as needed. The initial count number of the decreasing counter may be the initial amount or number itself in the case where the required accuracy of the remaining amount obtained by the remaining-amount obtaining device is low. However, in the case where the required accuracy is high, the decreasing counter must be set to an initial count number equal to a number obtained by adding, to the initial amount or number, the number of the ECs remaining between the EC-supply position and the connection portion at the time of detection of the connection portion. In either case, the present EC supplying apparatus can obtain the amount of the ECs remaining on the second EC tape. Otherwise, the remaining amount of the ECs on the second EC tape may be obtained by setting the counter to an initial count number when the remaining amount of the ECs on the first EC tape decreases to zero. However, since the present EC supplying apparatus sets the counter to an initial count number in response to the detection of each connection portion, the supplying apparatus can avoid the accumulation of errors and can obtain accurate remaining EC amounts. When a remaining EC amount decreases to a predetermined small amount, the supplying apparatus may inform an operator of the fact.
(21) According to a twenty-first feature of the present invention that includes the twentieth feature (20), the initial-amount obtaining device comprises an initial-amount input device for inputting the initial amount. The initial-amount input device may be a bar-code reader which is operated by an operator to read in a bar code representing the initial amount, or a keyboard which includes numeric keys and which is operated by an operator to input the initial amount. Thus, the initial-amount obtaining device obtains the initial amount. Otherwise, the initial-amount obtaining device may be one which reads out an initial amount corresponding to the particular sort of the second EC tape, from a memory of a computer which controls the EC supplying apparatus, or one which receives an initial amount from a computer different from the above computer.
(22) According to a twenty-second feature of the present invention, there is provided an electric-component supplying system comprising a plurality of electric-component supplying units each of which comprises an apparatus according to any one of the second to twenty-first feature (2) to (21); and a table which supports the respective frames of the electric-component supplying units, such that each of the respective frames attached to the table is detachable from the table, and such that respective electric-component-supply positions of the supplying units are arranged along a reference line on the table. The reference line may be a straight line, a full circle, an arc, or a curve, or a combination of two or more of them. Each of the first and second EC tapes may be stored in various manners, for example, wound on a supply reel, or stored in a storing container. Each of the EC supplying units may comprise a main frame which includes an EC storing portion, such as a supply-reel holding portion or a storing-container holding portion. Alternatively, each EC supplying unit may comprise an EC storing device separate from its main frame. The respective separate EC storing devices of the EC supplying units may be provided on the table with the respective main frames thereof, or may be provided away from the table.
(23) According to a twenty-third feature of the present invention, there is provided a method of feeding a plurality of electric-component tapes each of which includes a carrier tape and holds a plurality of electric components in a lengthwise direction of the carrier tape, supplying, from the each electric-component tape, the electric components, one by one, to an electric-component mounting system, and operating the electric-component mounting system to sequentially mount the electric components at respective positions on a print-wired board, thereby assembling an electric circuit on the print-wired board, the method comprising the steps of feeding the plurality of electric-component tapes including two electric-component tapes one of which holds a first sort of electric components and the other of which holds a second sort of electric components different from the first sort of electric components, supplying, from each of the two electric-component tapes, the electric components of a corresponding one of the first and second sorts, one by one, to the electric-component mounting system, connecting, to a terminal end portion of a first one of the plurality of electric-component tapes that currently supplies the electric components to the electric-component mounting system, an initial end portion of a second one of the plurality of electric-component tapes that holds the electric components of a same sort as the electric components held by the first electric-component tape, inputting, at a timing around a timing at which the first and second electric-component tapes are connected to each other, identification information identifying the second tape, into the electric-component mounting system, detecting a connection portion where the terminal end portion of the first electric-component tape and the initial end portion of the second electric-component tape are connected to each other, comparing, in response to the detection of the connection portion, the input identification information, with reference identification information pre-stored in the electric-component mounting system and, when the input identification information is not identical with the reference identification information, stopping the operation of the electric-component mounting system. According to this method, the EC mounting system is stopped when an incorrect sort of EC tape is connected to the first EC tape. Thus, the EC mounting system is prevented from mounting an incorrect sort of ECs on a PWB.
(24) According to a twenty-fourth feature of the present invention that includes the twenty-third feature (23), the step of inputting the identification information comprises reading in, with a bar-code reader, a bar code as the identification information identifying the second electric-component tape.
(25) According to a twenty-fifth feature of the present invention that includes the twenty-third or twenty-fourth feature (23) or (24), the assembling method further comprises a step of obtaining a remaining amount of the electric components which currently remain on the second electric-component tape, based on the number of the electric components supplied from the second tape after the detection of the connection portion and an initial number of the electric components which are initially present on the second tape connected to the first tape. The remaining amount of the ECs on the second EC tape can be obtained in the same manner as that employed in the EC supplying apparatus according to the twentieth feature (20). In the case where the remaining amount is controlled with accuracy, the number of the ECs present on the first EC tape between the EC-supply position and the connection-portion-detect position should be taken into account. However, in the case where no accurate remaining amounts are needed, the above number may be neglected.
(26) According to a twenty-sixth feature of the present invention, there is provided a method of feeding a plurality of electric-component tapes each of which includes a carrier tape and holds a plurality of electric components in a lengthwise direction of the carrier tape, supplying, from the each electric-component tape, the electric components, one by one, to an electric-component mounting system, and operating the electric-component mounting system to sequentially mount the electric components at respective positions on a print-wired board, thereby assembling an electric circuit on the print-wired board, the method comprising the steps of feeding the plurality of electric-component tapes including two electric-component tapes one of which holds a first sort of electric components and the other of which holds a second sort of electric components different from the first sort of electric components, supplying, from each of the two electric-component tapes, the electric components of a corresponding one of the first and second sorts, one by one, to the electric-component mounting system, connecting, to a terminal end portion of a first one of the plurality of electric-component tapes that currently supplies the electric components to the electric-component mounting system, an initial end portion of a second one of the plurality of electric-component tapes that holds the electric components of a same sort as the electric components held by the first electric-component tape, detecting a connection portion where the terminal end portion of the first electric-component tape and the initial end portion of the second electric-component tape are connected to each other, and obtaining a remaining amount of the electric components which currently remain on the second electric-component tape, based on the number of the electric components supplied from the second tape after the detection of the connection portion and an initial number of the electric components which are initially present on the second tape connected to the first tape.
(27) According to a twenty-seventh feature of the present invention that includes the twenty-sixth feature (26), the assembling method further comprises a step of informing, when the obtained remaining amount is not more than a reference amount, an operator of a fact that the obtained remaining amount is not more than the reference amount. The operator has only to connect another EC tape to the current EC tape, when he or she is informed of the fact that the remaining amount is not more than the reference amount. That is, the operator need not always monitor the remaining amount of the current EC tape. Thus, the operator can easily control the remaining amount of each EC tape. An alarm device, a display device, or both of them may be employed to inform the operator of the fact. Each of the twenty-third to twenty-seventh features (23) to (27) relating to the CB assembling method may be combined with each of the first to twenty-second features (1) to (22) relating to the EC supplying apparatus or system, so as to enjoy the effects and advantages of the each feature (1) to (22).